1. Field of the Invention
The present invention relates to a flexible top apparatus of a vehicle, as an automobile.
2. Description of Related Art
There is an automobile in which an upper portion of the vehicle chamber is open to thereby enjoy open air.
The automobile of the open air type requires a member for covering its vehicle chamber to be used when required or needed as when it rains. As such a member may be used a foldable or windable flexible-sheet, or a top.
Representative of such an automobile is one of full open type, which may be called a Cabriole type. An automobile of full open type as disclosed in U.S. Pat. No. 4,572,570 is basically of a type designed to allow an upper portion and a rearward upper portion of its vehicle chamber are fully open. More specifically, the automobile is provided with a front window glass panel, but no rear pillar is provided which is otherwise required in order to support the roof panel and a rearward end portion of the roof panel. Although the automobile of the full open type presents the advantage that its vehicle chamber can be widely open, it poses various difficulties at the same time that a rigidity of the vehicle body is hardly ensured because neither roof panel nor rear pillar are mounted, that the flexible top should be constructed in such a shape as covering the rearward upper portion of the vehicle chamber as well as the upper portion thereof when it is brought into a closed state, thus complicating its structure, and that a sealing performance of the flexible top is poor when it closes the vehicle chamber.
There is accordingly the increasing tendency that an automobile of a flexible top type which may be called of a canvas top type (see U. K. Patent Specification No. 1,315,364). The automobile of flexible top type or canvas top type is such that only an opening formed on a roof panel--such an opening being referred to herein as "roof opening"--is covered (closed) or uncovered (opened) with a flexible sheet so that this type may called a flexible top or a so-called flexible roof. The automobile of this flexible top type is provided .with a roof panel having a wide opening, or roof panel opening, connected to the vehicle body at least through front and rear pillars in such a manner that the roof panel opening is closed or opened with the flexible top. More specifically, the roof panel is of the type such that its whole middle portion is wide open as a roof panel opening except its front header, a pair of its left-hand and right-hand side rails, and its rear header. In other words, the front and rear headers and the side rails constitute a four-sided circumference of the roof panel opening and a front window glass panel is fixed with a pair of the left-hand and right-hand front pillars and the front header while a rear window glass panel is fixed with a pair of the left-hand and right-hand rear pillars and the rear header.
As the flexible top is in a closed state in which it fully closes the roof panel opening, the flexible top is designed such that its forward end is brought into abutment with the front header of the roof panel, its left-hand and right-hand side end portions are in abutment with the left-hand and right-hand roof side rails, and its rearward end is abutted with the rear header. This arrangement ensures a rigidity of the vehicle body to a sufficient extent because a framework of an upper circumference of the vehicle chamber is constituted by the left-hand and right-hand front pillars, front header, left-hand and right-hand roof side rails as well as rear header, such members being connected to each other. This structure further provides the advantage that it is simple because the flexible top is designed simply to open or close the roof panel opening. Furthermore, it presents the advantage that most common automobiles with a roof panel supported with front and rear pillars can be converted to those of flexible top type by small modifications. For the above reasons, recently, there is the tendency that automobiles of flexible top type increase dramatically.
The automobile of the flexible top type is designed so as to take a closed posture, or to become in a closed state, in which the roof panel opening is closed by fixing a rearward end portion of the flexible top to the rear header while abutting a forward end portion of the top with the front header, on the one hand, and so as to take an open posture, or to become in an open state, in which the roof panel opening is wide open by transferring the forward end portion of the top rearwardly to a large extent from the closed posture toward the rear header. At this open posture, the flexible top is housed or accommodated in a folded or wound state.
For the automobiles of conventionally flexible top type, however, the flexible top in a housed state is still extended wide in a longitudinal direction so that it covers over a considerably large portion of the roof panel opening, thus impairing a sufficiently open feeling. It is further to be noted that, as the roof panel opening is open while the flexible top is housed, the flexible top is in a state that it projects upwardly to a considerable extent, thus resisting air during running so that it increases a resistance to air and it causes running noises derived from wind-blowing.
Proposals have been further made of an automobile positioned in between the flexible top (canvas top) type and the full open type. Japanese Patent Publication (Kokai) 162,326/1988 proposes the type in which a rearward opening surrounded by the rear header and a pair of the left-hand and right-hand rear pillars is opened or closed, too, by a top composed of a flexible sheet, in addition to the roof opening surrounded by the front header, a pair of left-hand and right-hand roof side rails, and the rear header. For this type of the automobile, the flexible top is accommodated at a position nearby or close to a lower end portion of the rearward opening so that this type is advantageous in terms of an open feeling and a resistance to air. However, it is considerably difficult to ensure a complete sealing for closing the roof opening and the rearward opening because the flexible top should close the both openings and because a plane containing the roof opening is connected to a plane containing the rearward opening at a relatively sharp angle. Furthermore, the flexible top should be considerably large enough to cover the both openings and the structure for accommodating such a large flexible top should also be rendered complicated. On top of that, the flexible top should be provided with the function which serves as a rear window glass, too.